Elevating truck



Dec. 31, 1929. D. E. HENNEssY ELEVATING TRUCK Filed Feb.' s, 1928 5 sheets-sheet lnvenTor'. Daniel E.Hennssy bym MIM.

' l AlTyS Dec. 3l, 1929. D. E. HENNEssY 1,741,712

` ELEVATING TRUCK Filed Feb. 3, 1928 s sheets-sheet 2 Dec. 3l, 1929.

ELEVATING TRUCK Filed Feb. 5,' 1928 Fig. 5.39

WWW/1am A Invenor.

Daniel E. Hennessy Patented Dec. 31, 1929 UjNIi'sED STATES T QFFIQE DANIEL E. HENNESSY, OF CAMBRIDGE,

MASSACHUSETTS, ASSIGNOR T0 LEWIS- SHEPARD COMPANY, or WATERTOWN, Messao'nnsn'rrs, vA eearonftrfren or Mas- SACHUSETTS ELEVATING TRUCK rl"his invention relates to improvements in elevating trucks having upwardly movable load supporting means and means operable by the vertical swinging movement of the handle 5 to lift the load supporting means.

One of the principal objects of the invention is to provide means for applying the lifting force vertically 4and directly to the load supporting means and so arranged that the load can be raised .by a vertical swinging movement of the tongue when the tongue is in anv steering position.

A further object of the invention is to provide an elevating truck with lifting mechanismoperable by atongue which is free from any inter-mediate positive or interengaging connection to the load supporting means, whereby the lateralsteering movementof the tongue is unhampered and the tongue capable of being moved freely through a steering range of approximately one hundred eighty7 degrees.

A further object of the inventionfistopro vide lifting mechanism operable-.by the tongue which will require a minimum amount vof head room and less than that required by trucks heretofore constructed.

In elevating trucks vheretofore .constructed the greaterportion of theweight of theload iscarried upon the rear axle of the truck. A further important object of the invent-ion is to provide a censtruction which will more nearly `eopialize the distribution .of the weight upon the steering mechanism Aand the rear axle.

A furtherimportant object ofthe invention is to provide anelevating truck construct-ion in which the vertical swinging movement of .the tonguewillapply a greaterlifting leverage to the load supporting means than has heretofore been accomplished.

Another important object .of the invention is` to provide an .elevatingtruck .construction in which the lowering of fthelead can .only :be .accomplished when vthe lifting mechanism is engaged .by the tongue and .under the control ofthe operator.

Another important object efztheinvention is to provide novel lmeans Yfor freeing l the tonguefroin operativeen-gagement with other 3, 192,8. Serial No. 251,694.

members of the lifting mechanism, while maintaining afrelation therebetween by means of which the lifting mechanism may be reengaged automatically by a full upward movement of the tongue when in any steering position.

Another object of the invention is to pro vide manually operable means for releasing the lifting mechanism from the tongue which can only'be operated to free the tongue when Y the load supporting means is locked in elevated position, or is in lowered position, and which cannot be re-.engaged until the .tongue is swung to substantially full upward 'position, whereby `inj ury to the operator, by aflying tongue, will be avoided.

.'A further objectoftheinvention is to provide novel mechanism for locking the load supporting means in elevated positionlocated centrally of the width of the load supporting meansthereby avoidingtwisting strains upon the frame Vand load .supporting means which are inherent in usual elevating .truck .constructions.

A further object of the invention is to pro vide a novel locking deviceautomatically operable tolock the load when raised to elevated position .with manual means operable when the load supporting means is locked in ,ele-

'vated position-to eXerta force` upon the lock- .ing means-tending to unlock the same when the locking mechanism `is relieved of lthe 4weight .of the load by slightly elevating the .lead vsupporting means.

A further 4obj ect ofthe invention is to proyide an elevating truck having load supportingmeansmounted upon parallel *links and adapted to move vertically and longitudinally with lifting mechanism operable to apply vertical lifting force directly to the front vide Aa novel and improved bearing between the load supporting means and the upper ends of the rear pair of parallel links.

A further and very important object of the invention is so to mount the lower ends of the rear links upon the aXle that during the lifting of the load supporting means the weight of tlie-rear end of the load supporting means and of the load thereupon will be imposed upon the bearings of the rear wheels and rotatable in such bearings, which preferably are roller or other anti-friction bearings.

Another object of the invention is to provide means for preventing tilting of the load supporting means when the load supporting means is elevated with the tongue at the side.

rlhese and other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be particularly pointed out in the claims.

A preferred embodiment of the invention is illustrated in the accompanying drawings, in which,

F ig. 1 is aplan view of an elevating truck embodying the invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a front end elevation thereof;

Fig. l is an enlarged detail View of the front end of the truck, mainly in longitudinal vertical section, showing the load supporting means looked in elevated position with the lifting mechanism in engagement with the tongue, but in an intermediate position, adapted to permit the tongue to be swung freely to any steering position, or upon depression of the tongue to engage-the load supporting means in preparation for the lowering of the same;

Fig. 5 is an enlarged detail view, similar to Fig. 4L, of the front end portion of the truck showing the tongue depressed, with the lifting mechanism engaging the load supporting means and with the load supporting means locked in elevated position;

Fig. 6 is a similar view showing the tongue disengaged from the lifting mechanism and the load supporting means in loweied position;

Fig. 7 is a detail view illustrating the locking member in normal position and ready to engage a shoulder upon the front end of the load supporting means when the latter is raised to elevated position;

Fig. 8 is a similar view showing the load supporting means locked in elevated position with the means for actuating the load supporting means in a position tending to release the locking mechanism upon slight. elevation of the load supporting means;

Fig. 9 is an enlarged detail sectional viev7 illustrating` in section one of the rear pair of parallel links, the upper connection thereof to the load supporting means and' the lower end of the link so mounted upon the rear axle that upon upward movement of the load supporting means the weight of the load will be imposed upon the bearings of the rear wheels; Y

Fig. 10 is an enlarged detail view of th locking dog and the locking dog actuating mechanism Y Fig. 11 is a detail view in horizontal section of the means for securing the legs,

which prevent tipping of the truck, in inoperative position; and

Figure 12 is a detail view illustrating the manner in which the pivots for the front links are secured in the bosses upon the lifting head.

The elevating truck comprising the present invention includes essentially supporting wheels and steering mechanism having a tongue or lifting lever mounted to swing vertically, load supporting means and means operable by the vertical swinging movement of the tongue to apply a lifting force vertically and directly to the load supporting means.

A particular embodiment of the invention illustrated herein comprises a truck having a. frame provided with a headcomprising a central, substantially annular, body 1 formed integral with front and rear arches 2 and 3 which are connected together by integral side members 4 and 5. Horizontal side bars 6 and 7 extend rearwardly from the head .and are connected together by a cross girder 8 which is located at a short distance from the rear end thereof and preferably is welded to the side bars. An axle 9 is rotatably journalled in the side members 4 and 5 at.

their rear ends, for purposes which will hereinafter more fully appear, and wheels 10 and 11, preferably having anti-friction bearings; are rotatably mounted upon the axleV intermediate of the side bars 6 and 7.

Suitable steering mechanism is rotatably mounted in the head of the frame. As illustrated herein the steering mechanism comprises a steering post 12 which is rotatably mounted in the body 1 of the head and is provided with an annular iiange 13 which underlies the same. Arms 14, which are i tegralfwith the fiange 13, extend downwardly therefrom and are provided with bosses which embrace a sleeve 15 which forms the bearing for an axle 16 upon which the front steering wheels 17 are mounted. A split collar 18 embraces the steering` post 12 and is provided with forwardly extending flanges or arms 19 which are clamped together by a bolt 2O, thereby clamping the collar firmly upon the steering post.

The collar is provided with a pair of upwardly, and preferably forwardly, extending arms 21 having at their upperends bosses upon which the shaft 22 of the tongueis pivioo iio

oted. The tongue illustrated is formed of a tube 23 having at its free end a hand-.gripping member 2a extending transversely thereof and secured thereto by a suitable coupling 25, and at its lower end a base member, desirably a forging, having a split socket 26 to receive the tonguemember 23, and a bifurcated portion the arms 27 of which are pivoally mounted upon the shaft 22. The tongue thus mounted may be swung laterally to steer the truck and may also be swung vertically.

Suitable lifting mechanism is provided which is `operable by a vertical swinging movement of the tongue, preferably a downward swinging movement thereof, to apply 'u a lifting force vertically directly to the load supporting means. rEhe preferred lifting mechanism which is illustrated herein comprises a lifting lever 28 which is fulcrumed upon the shaft 22 upon which the tongue is pivotally mounted and means are provided for releasably connecting the same to the tongue so that when thus connected the lifting lever will form in effect a portion, preferably an extension, of the tongue. Y

'Desirably means are provided for detachably connecting the lifting lever to the tongue. In the particular construction illust-rated the lifting lever comprises two parallel -arms which are connected. at their front ends by an integral transverse member 29 having a forward latch-engaging extension 30. The opposite end of the lever 28 is so constructed as toengage the load supporting means in substantially a line contact so that upon depression of the tongue the lifting force will be applied vertically to the load supporting means.

In the preferred construction shown herein this line contact is produced by a roller 3l which is journalled upon a shaft 32 mounted in the arms 28 of the lifting lever. The arms 28 of the lifting lever project a sufiicient distance beyond the roller 31 to engage the upper face of the collar 18 when the tongue is raised substantially to vertical position, thereby to form a rigid engagement which will enable the truck to be pushed rearwardly by pressure applied to the tongue. The arms 28 of the lifting lever desirably are provided with curved lower faces which provide a guide for the latch which detachably connects the tongue to the lifting lever.

The preferred form of latch which is illustrated herein comprises a forging having a U-shaped arm 33, the transverse member 34 of which is adapted to engage a notch 85 on the under face of the arms 28 of the lifting lever and also to engage the extension of the cross member 29 of said lifting lever. The latch is provided with lan angularly bent actuating arm 36 the end portion of which extends in a general direction of and beneath the base portion of the tongue. The latch is so constructed that the raction of gravity causes the vtransverse member 34 of the latch to ride upon the curved faces of the lifting lever and when the ltongue is raised yto the full limit of its upward movement to cause the cross member 8l of the latch to engage `,the notch on the liftinglever and-also the projection 30 of the lifting lever. lVhen the latch isl released to free the .tongue from the lifting lever and the tongue is swungdownwardly to steering position, the latch will ride upon the curved under faces of the lifting lever which will prevent engagement of the latch vunless anduntil the tongue is swung to the lfull upward limit of its movement, at which time the projections on the end of the tongue will engage the top of the collar 18 and cause such relative movement between the tongue and the lifting lever that the transverse member of the vlatch will come into alinement with the notches of the lifting lever, and automatically lock therein.

j By virtue of this construction the latch of the tongue can be engaged with the lifting lever only when the tongue is at the limit of its upward movement, at which timethe load supportingmeans is in lowered position, -or is locked in fully elevated position. 'Consequently,.the ydropping of the load supporting means by the accidental release of its'locking mechanism cannot cause the tongue to ily yupwardly and injure the operator or a byg stander. Furthermore,.as the latch on the tongue automatically engages the lifting lever when the tongue is kswung to full upward position, the load must`be`lifted upon depression of the'tongue unlessthe operator manually releases the latch. Consequently such injury to the operatoris avoided as frequently occurs lin the operation of trucks, which'requi-re manual operation of means to connect the tongue tothe load supporting means where the operator, failing to ma'l'ea proper connection, applies the weight of 'his body to an unresisting tonguewith such impetus 'as to throw him onhisbac'k upon the floor. v

The lifting construction thus described may be built into a very much smaller spacethan has heretofore been possible and furthermore is so designed as to provide a much greater lifting leverage by the actuation of the handle than in trucks of the prior` art, thereby providing a truck having a much easier lift than has heretofore been produced. Inasmuch as the lifting mechanism is so constructed as to apply a vertical lifting force to the load supporting mechanism, the load supporting mechanismextends over the effective portion or yextension of the r-lifting lever 4and vpreferably p'resents a flat surface to be engaged by the roller 31 of the lifting lever, although it will be understood that other suitable antifriction means may be provided, or that a roller may be journalled in the load supportingmeans and cooperate witha suitable complementary surface upon the lifting lever within the scope of the invention.

Any suitable form of load supporting means may be provided with suitable means to guide the same during the lifting movement thereof. In the preferred construction illustrated heiein the load supporting means is in the form of a platform guided upon parallel links to cause a longitudinal, as well as a vertical, movement thereof. lt comprises a head consisting of a cross girder 37, a central upwardly extending standard 38, a forward extension 39 presenting a flat under face 40, arch members 4l extending laterally from the standard and forwardly extending side arms 42, all of which desirably are integral in construction. Side bars 43, which are rigidly secured to the side members 42 by rivets or welding, or both, extend rearwardly from the head and are connected about midway of their length by a transverse, preferably inverted, channel shaped girder 44, and at their rear ends by a vertical channel bar 45 which desirably is welded at its ends to the ends of the side bars. The front end of the load supporting means is connected to the head of the frame by parallel links 46, and the rear end of the load supporting member is supported and guided upon rear parallel links 47.

rlhe under face 40 of the forward extension 39 of the head overlies the lifting lever of the tongue and preferably, but not necessarily, overlies the axis of the steering mechanism, and the lifting lever desirably is so fulcrumed that the roller 3l engages the fiat face 40 of the lifting head in approximately the direction of the axis of the steering mechanism, so that whatever the position of the tongue when it is swung vertically, the roller will engage the flat under face of the lifting head of the load supporting means in a line of contact which is at or near the vertical axis of the steering mechanism. However, it will be readily understood that by providing the lifting head with a flat under face of sufficient width, the lifting member may be so journalled that the roller will swing laterally through an arc of greater length so long as it maintains a line of contact with the under face of the lifting head.

@ne of the features of the invention consists in providing a construction which will enable the application. of a greater lifting force at the starting of the lifting operation than during its continuance. rljhis is accomplished in the present construction by constructing the lifting lever that the line or coin tact between the lifting lever or the antifriction roller thereupon will be nearer the vertical axis of the fulciuin of the lifting lever at the beginning and during the oo ntinued lifting movement of the lever. It will be observed from reference to Figs. 4 and` 5, and 6,'that when the load supporting means is in its lowered position, as illustrated in Fig.

6, the line of contact between the roller 3l and the flat under under face 40 of the lifting head, which is directly over the axis of the roller 31, is in proximity to the vertical plane of the axis of the shaft 22 whichv forms the common fulcrum'for the tongue and lifting lever, and that as the tongue is depressed during the lifting operation the axis of the roller 3l swings upwardly through the lower quadrant of an arc so that when the axis of the roller 3l is in substantialy the same horizontal plane as the axis of the fulcruin 22, the effective distance between the vertical plane of the line of contact of the roller 3l and the face 40 of the lifting head, will be considerably increased, and that upon further upward movement to elevated position, as illustrated in Fig. 5, the axis of the roller 3l will have slightly approached the vertical plane of the axis of the fulcrum 22. ln the particular truck, from which the drawings herein are made, the distance between the axis of the fulcrum 2:2 and the axis of the roller 3l is approximately one and one-lialf inches, which represents the effective length of the lever extension beyond the fulcrum when the'axis oi the fulcrum 22 and th-e roller 3l are in the same horizontal plane. lhen, however, the load supporting means is in its lowered position, as illustrated in Fig. 6, the distance between the vertical plane of the axis of the fulcrum and the vertical plane of the axis of the roller 3l is approximately one inch. ln each case the effective length of the tongue or lever arm to which the force is appli-ed is the same so that obviously 'a much gieatei lifting leverage is obtained during the starting of the lifting movement than during the continuation thereof. This is particularly important for the reason that when the load is started the tongue is in elevated position which renders the application of force thereto less advantageous than when the tongue is brought down to a point at which the operator can place the weight of his body upon it,

As heretofore stated the lifting head of the load .supporting means is formeel integral and the side bars 43 rigidly secured thereto, and also rigidly secured together by intermediate and end girders 44 and 45, so that the load supporting means is in effect an integral unit, and it will be understood that the term integral used in the claims includes a permanently rigid construction of this character as distinguished from any construction comprising a yielding, pivotally mounted, or otherwise flexibly movable member.

By forming the head with a forwardly projecting portion overlying the lifting lever th-e necessity of intermediate permanent universal or detachable interengaging` connections between the load supporting Ameans and the lifting mechanism or steering mechanism is entirely avoided and thetongue is given a free range of steering movement of Cil .i reduced to a minimum.

approximately one hundred eighty degrees. Such construction is believed to be wholly novel and in combination with th-e'mecha nism tor applying vertical lifting movement to the load supporting means provides new and ac vantageous features ot operation. It permits the construction ot a truck with less head room. lt enables the trent end et the load supporting means to be brought in greater proximity to the steering mechanism so that a greater portion of the load may be carried thereby than in previous elevating truck constructions in which approximately seventy-live per cent et the load has been carried by the rear axle. lt enabl-es the front end et the load supporting means to be rai-sed in such a manner that the front pair ot parallel links are relieved ot compression and the wear upon the ournals and bearings thereof By reason ot the application of a vertical torce directly to the load supporting means, particularly through the line of contact with an anti-triction'roller, the horizontal component o t' the torce heres tot-ore required to raise the platform upon parallel links is largely eliminated and a greater' eiitective lifting torce consequently obtained.

Another important feature of the invention resides inthe construction and arrange-y ment ot the rear pair of parallel links. This mechanisn'i is so designed as to increase the etlective bearing surface of the upper ends the links and to cause the lower ends et the links to transmit the weight ot the rear end -ot the load supporting means, and the load thereupon, directly to the axle et the rear wheel which is rotatable in the bearings et such wheels which preferably are antitriction bearings.

ln the particular construction illustrated the upper ends ot the links 47 are preierably provided with inwardly extending bosses which are connected by a spacing sleeve 48 which is welded to said bosses, and the spacing sleeve and bosses are rotatably mounted upon a shaft 49 which desirably is welded at its ends to the side bars 43 ot the load supporting means. 'lhe sleeve 48 dcsirably is provided with one or more oil holes to per- `t the introduction ot a lubricant and may dcaied be provided with suitable means to i. ci .ntroduction et grease under pressure. The lower ends of the links 47 are likewise provided with inwardly extending bosses 50 which abut against washers 5l desirably countersunk in the .outer ends ot the hubs 52 ot the rear wheels l0. lVashei-s 53 desirably countersunk in the opposite ,ends of the hubs 52 and with the washers 51 form enclosures tor the ends of roller bearings 54. Other washers 55 overlying the inner .ends of the hubs engage the washers 53 and. abut against the ends ot a spacing sleeve 56 which encloses the rear axle 9 and desirably is secured thereto as by a cotter pin 58, (see Fig. l). The ends ot the shaft 9 are rotatably mounted in the side bars 4 and 5 of the main trame. By reason ot this construction the links 47 and sleeve 48 provide a long bearing tor the upper end ot the link which is secured to the load supporting means. As the lower ends of the links 47 are mounted directly upon'the axle 9, the ends ot which are rotatable in the side bars 4 of the main vtrame, the weight of the load is imposed during the raising and lowering movements of the load supporting means directly upon the axle 9 and the friction between the lower ends of the links 47 and the axle 9 will cause the same to rotate within the anti-friction bearings ot' the rear wheel l0 as the load supporting means is raised and lowered, thereby reducing the friction to a minimum and also entirely avoiding wear upon the bearings oi the axle 9 in the side bars. By reason ot this construction no substantially heavy transverse torce `vill be applied to the side bars'6 and 7 ot the trame and these members will be subjected practically entirely to longitudinal strains, thus enabling them to be made of relatively lighter construction than in previous trucks et this type.

A further important feature ot the invention relates 'to the mechanism for locking the load supporting means in elevated position and comprises a locking dog which is located centrally ot the width ot the load supporting means and acts to stab'lize the strains upon the load supporting means when locked in elevated position, as distinguished from prior constructions in which the locking mechanism is located at the side of the longitudinal center ot the load supporting means and transmits a considerable. strain to the load supporting means and the trame. In the present construction the front face of the standard irovided with a preferably vertical tlat tace 59 having at its lower end a shoulder 60 adapted to be engaged by a locking latch or dog'. The locking latch or dog desirably is in the 'torni ot a iiat plate 6l having` at its lower end laterally extending cylindrical members torining pivotal shafts 62 and 63 `which are journalled in suitable bosses 64 and 65 'formed integral with and extending upwardly from the body l ot the head. @ne ot these bosses 64 desirably is biturcated to present an open slot so that the cylindrical shaft 62 may be passed through the bearing in the boss 64 yand the other cylindrical shaft 63 thereupon dropped down through the open slot into the boss 65 and retained therein by a Cotter pin 66, thus providing a ready means of assembling the locking dog or latch upon the head.

The cylindrical shaft 62 is provided with a pin 67 which extends therethrough and lis adapted to b e engaged by a spring controlled dog-actuating device which normally tends lilo to force the dog toward engaging position, but when the load supporting means is locked in elevated position by the dog is adapted. to be so actuated as to exert a force upon the locking dog tending to withdraw it from locking position, so that upon sufficient elevation of the load supporting mea-ns to remove the weight of the load from the latch it will automatically swing out of engagement with the locking shoulder 60 of the lifting head and permit the load supporting means to be lowered under the control of the tongue.

The dog-actuating device is particularly illustrated in Figs. l, 2, 7, and 8. It comprises a horizontal substantially U-shaped lever, the inner arm 68 of which is pivotally mounted upon the cylindrical shaft 62 of the locking dog which projects beyond the boss 6e and is provided with a transverse pin 67. The transverse member 69 of the U-shaped latch-releasing lever extends in parallelism with the lifting head and the other arm 70 of said lol-shaped lever extends forwardly and is provided at its end with an upwardly and inwardly extending projection forming a foot pedal. rlhe transverse member 69 of the dog-actuating means is provided with a forwardly extending lug 7l which is adapted to be engaged by a movable member of the load supportingr means, such as the transverse arch of the lifting head during the lowering of the load supporting means, and is operable thereby to restore the dog-actuating mechanism to normal position as will hereinafter more fully appear.

The arm 68 of this dog-actuating lever has an inwardly extending boss 72 which embraces the cylindrical shaft 62 of the locking dog 6l and which is cut away on opposite sides of tl e pin 67 to provide shoulders 73 and 74 to engage the pin respectively when the dog-actuatin g member is swung on opposite sides of the axis of the shaft 62. A helical spring 75, which is secured at its lower end to a pin 76 on the rear arch 3 of the truck frame, is secured at its upper end to a pin 77 projecting outwardly from an extension 7 6 of the boss 72 which is journalled upon the shaft 62. rll`he anchoring pin 76 desirably is located in approximately the vertical plane of the axis of the shaft 62, while the pin 77, to which the upper end of the spring is secured, is adapted to swing upon either side of the vertical plane of the axis of the shaft 62. When in the normal position illustrated in Fig. 7 the spring acts at the rear of the vertical plane of the center of the shaft 62 and forces the latch into engagement with the flat front face 59 of the standard 38 ofA the lifting headso that when the load lsupporting means is raised to its elevated position the dog 6l will be forced into engagement with the shoulder 60 of the lifting head and when so engaged will stand approximately vertically, thereby locking the load supporting means in elevated position. Vhen the tongue is thereafter elevated the weight of the front end of the load supporting means will be sustained upon said dog and the tongue may be freed from the lifting mechanism for steering purposes.

Any time after the weight of the load supporting means is thus imposed upon the dog 6l, the pedal member 70 of the dog-actuating lever may be depressed by the' foot, thereby swinging the spring 7 5 to the other or forward side of the vertical axis of the shaft 62, as illustrated in F ig. 8, whereupon the spring will impose a tension upon the locking dog tending to release the same. The tension thus imposed upon the dog, however, is wholly insuflicient to remove the dog from locking position when the weight of the load is upon it. However, when the lifting head of the load supportingmeansis again engaged by the lever, upon downward swinging movement of the tongue, and slightly lifted, the tension of the spring 7 5 will throw the dog out of engagement so that the load supporting means may be lowered under the control of the operator.

A further feature of the invention consists in providing means for preventing the tilting of the truck when the load is lifted, with the tongue at the side. Any suitable means may be employed to accomplish this purpose. A simple and convenient device which is illustrated herein comprises al pair of legs 79 pivotally connected to the side bars 6 and 7, preferably in substantially the vertical transverse plane of the axis of the steering mechanism, and of such length that the lower ends will slightly clear the floor. These legs will swing' freely forwardly or rearwardly upon engagement of any obstruction during the moving of the truck, but will normally be held by gravity in a vertical position so that when the handle is swung to the side and a litfing force applied thereto, the leg on the side toward which the handle extends will engage the floor, if the pressure upon the handle is suliicient to tilt the truck, and prevent further tilting thereof.

If desired means may be provided for holding the legs in horizontal position in parallelism with the side bars 6 Aand 7. A convenient device for accomplishing this purpose, which is illustrated in the accompanying drawings, comprises a ball 8O which is reciprocably mounted in a hole drilled into the side frame and retained therein by slightly closing the mouth of the recess, as for example by peening the wall thereof so that a portion of the ball will project beyond the plane of the side bar, but will be held from escape by the peened edge of the wall. A helical spring, located within the drilled hole and engaging the ball, normally holds the same in extended position. The leg 79 is provided with a slight recess 8l adapted to engage the ball when the leg is swung to elevated position. lBy reason of this construction it is only necessary to swing the leg to elevated position, whereupon the ball will enter the recess sufficiently to retain the leg in such position. It can, however, be readily detached therefrom by merely stepping on the leg with sufcient force to force the ball backwardly against the tension of the spring and the leg will then drop to its vertical normal position.

rllhe elevating truck disclosed herein is so designed as to present an exceedingly rugged construction and also to permit easy replacement of broken or worn parts. 'ihe fulcrum shaft of the tongue and lifting lever is heid in lace by Cotter pins as is also the shaft 32 of the lifting roller. The front links 46 are pivotally mounted both at their upper and lower ends upon pins 461 which are secured respectively in bosses upon the arched lifting head of the load supporting means and upon the head of the truck frame. These pins are provided at their inner ends with enlarged knurled heads 462 which are driven into the inner bosses to prevent rotation of the pins, and at their outer ends are welded in one or more spots 463 respectively to the frame and to the side bars 4of the platform. 'By reason of this construction the pins can be easily re moved by cutting off the welding at the outer ends of the pins with a cold chisel and driving upon the outer ends of the pins with a suitable tool. The shaft 49 at the rear end of the load supporting means is retained in position by spots of welding at its outer end and these welding spots can be readily chipped olf with a lcold chisel and the shaft removed when worn. All rigid parts of the truck desirably are secured together by weld ing in addition to such rivets as may be conveniently employed so that the Yframe and the load supporting means respectively are in effect of integral construction. The tongue and lifting mechanism are carried by a collar which is Icramped upon the steering post by a single bolt which may be easily removed to permit the steering head to be dismantled, and the front wheels of the steering mechanism, lwhich are provided with ball bearings, are held upon their respective shafts by washers and cotter pins located in recesses in the wash ers and extending through the outer ends of the shaft. It will, therefore, be obvious that any damage to the truck can be readily repaired. Y

The operation of the truck may be briefly described as follows: Assuming that the load supporting means of the truck is in lowered position and the handle freed from the lifting mechanism, as illustrated in Fig. '6, the truck will be backed beneath the loaded platform. The tongue will then be swung to full upward position at which time the U-shaped latch Se will ride upwardly along the curved surface of the lifting lever 28 and the transverse member thereof will automatically engage the notches 35 of the lifting lever and also beneath the extension 30 of the lifting lever, thereby locking the lifting lever to the tongue so that it will form an extension thereof. The axis of the lifting roller 3l will then be in proximity to the vertical plane of the axis of the com-mon fulcrum 22'of the lifting lever and tongue. Downward swinging movement of the tongue will, therefore, raise the roller 3i through the lower quadrant of an a 1c, thereby causing a greater lifting leverage to be applied at the starting of the lifting of the load supporting means than during the continued movement of the tongue. rlhe antifriction roller 3l will exert the lifting force vertically upon the under flat face of the lifting head of the load supporting means. By reason of this action the full weight of the front end of the load supporting means is carried directly upon the steering mechanism. As the load supporting means is thus elevated, the parallel links 4G and 47 cause a longitudinal movement of the load supporting means. Such longitudinal movement is permitted as the flat under face of the lifting head rides forward upon the roller 31. During such movement the front links 46 are placed under tension whilethe rear linksare under compression. Inasmuch as the rear links are mounted at the lower ends upon the rotatable rear axle practically no frictional resistance is offer-ed to the swinging movement of the rear links 47 and the entire weight of the rear end of the load supporting means iscarried directly upon the axle without any transverse strain being imposed upon the side bars 6 and 7 of the frame. During the vertical and forward movement of the load supporting means the locking dog 6l rests against the vertical front face of the standard 38 and when the load supporting means has reached a predetermined elevated position the looking dog 6l engages beneath the shoulder, as illustrated in Figs. 2 and 5, thereby locking the load supporting means in elevated position. The operator may then release the tongue from the lifting lever by raising the arm 36 of the lifting lever so that the tongue will be freed for stee 1ing purposes. inasmuch the latch cannot be re-engaged by the lifting lever until the handle is swung to full upward position. any danger of injury by a flying tongue, when the tongue is not under the control of the operator, is avoided.

After the load supporting means has been locked in elevated position the operator may at any time depress the pedal 7l of the latch actuating mechanism thereby swinging the same about its pivot to position the spring in front of the vertical axis of the shaft 62, thereby imposing a tension upon the locking dog tending to remove it from locking position. W7 hen it is desired to lower the load 'the tongue will be again swung to vertical position to cause the latch to engage the lifting lever as aforesaid and the tongue depressed sufficiently slightly to raise the load supporting means, whereupon the tension of the spring T5 will throw the locking dog out of locking position, thus enabling the loa-d to be lowered under the control of the operator. During the downward and rearward i'novemcnt of the platform, as the load supporting means is lowered, the lug 71, which projects forwardly from the horizontal portion of the dog-actuating lever, will be engaged by the vei'tical arch 4l of the lifting head, and upon further rearward movement of the platform such'engagement will swing the loch actuating mechanism rearwardly so that the upper end of the spring 7 5 will again be positioned rearwardly of the axis of the shaft 62, thereby restoring the locking dog to normal position in which it is ready to engage the shoulder of the lifting head when the load supporting means is again elevated.

It will be understood that the particular embodiment of the invention disclosed herein is of an illustrative character and is not restrictive, and that various changes in form, construction and arrangement of parts may be made within the spirit and scope of the following claims.

Having thus described the invention what is claimed as new, and desired to be secured by Letters Patent, is:

l. An elevating truck comprising supporting wheels and steering` mechanism having a tongue mounted to swing vertically, an integral load supporting unit, means operable by a vertical swinging movement of the tongue when in any steering position to engage and then to apply vertically a lifting force directly to said load supporting unit.

2. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, an integral load supporting' unit, means operable by a vertical swinging movement of the tongue when in any steering position to engage and then to apply vertically a lifting force directly to an end of said load supporting unit and means for causingl longitudinal movement of the load supporting unit dui'- ing the raising and lowering` movements thereof operable to equalize the movements of both ends of said loan supporting unit.

3. An. elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, provided with a lifting member, having a free end, a rigid load supporting unit overlying the free end of said lifting member and free from positive connection therewith, and (Jo-operating means upon the free end portion of said lifting member and said load supporting means operable by a vertical movement of said tongue when in any steering position to apply vertically a lifting force directly to said load supporting unit.

4. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, a pivotally mounted lifting member forming an extension of said tongue and presenting a free end, means -detachably connecting said lifting member to said tongue, a load supporting unit overlying the free end of said lifting member and co-opei'ating means upon the free end of said lifting member and said load supporting unit operable by a vertical swinging movement of said tongue to apply vertically a lifting force directly to said load supporting unit.

5. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, apivotally mounted lifting member forming an' extension of said tongue and presenting a free end, anti-friction means mounted on said free end, means detachably connecting said lifting member to said tongue, a load supporting unit having a portion presenting a flat face,

overlying the free end of said lifting member and adapted to be engaged by the anti-friction means thereof whereby upon vertical swinging movement of said tongue sai-d fiat face will be engaged by said anti-friction mea-ns and a vertical lifting force applied to said load supporting unit and means for moving said load supporting unit longitudinally during the raising and lowering movements thereof.

6. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, load supporting means having an integral lifting head overlying said steering mechanism, a lifting lever operable by a vertical swinging movement of said tongue to apply a vertical lifting force to said lifting head in approximately the direction of the axis of said steering mechanism and means for releasing said lifting means from operative relation to said tongue.

7. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, load supporting means having a liftingrhead integral therewith overlying said steering mechanism, a lifting lever pivotally mounted upon said steering head and forming an extension of said tongue having means to engage and apply a vertical lifting force to said lifting head in approximately the direction of the axis of said steering mechanism and means for releasably connecting said lifting lever to said tongue whereby said lifting lever may be actuated by the vertical swinging movement of said tongue to lift the load supportin T means or released to permit free steering movement of the tongue.

8. An elevating truck comprising wheels and steering mechanism having a tongue pivotally mounted to swing vertically and having a steering range of approximately 180o, load support-ing means having a lifting head presenting a flat under-face overlying the vertical axis of said lifting lever fulcrumed on the pivotal support of said tongue and having an arm provided with means slidably and rotatably to engage said fiat face approximately in line with the axis of said steering mechapism and means for detachably connecting said lifting lever to said tongue whereby said lifting means may be removed from engagement with said flat face to permit free steering movement of the tongue.

9. fin elevating truck comprising wheels and steering mechanism having a tongue pivotally mounted to swing vertically and having a steering rang-e of approximately 1809,-load supporting means having a lifting head presenting a fiat under-face overlying the vertical axis of said lifting lever fulcrumed on the pivotal support of said tongue and having an arm provided with means slidably and rotatably to engage said flat face approximately in line with the axis of said steering mechanism, means for locking the load supporting means in elevated position and interengaging members on said lifting lever and tongue adapted to be released only whenthe load supporting meansis in lowered position or locked in elevated position.

10. An elevating truck comprising supporting wheels and steering mechanism provided with a tongue pivotally mounted to swing vertically, load supporting means having a lifting head presenting a flat face overlying the axis of said steering mechanism, a lifting lever fulcrumed on the pivotal support of said tongue and detachably connected to said tongue having an arm provided with an anti-friction roller adapted to engage the fiat under-surface of said lifting head and movable by a vertical swinging movement of the tongue from a position in proximity to the vertical plane of the fulcrum of said lifting lever to a position more remote therefrom, whereby greater leverage will loe applied to said lifting head at the beginning of the lifting movement than during the continuation thereof.

11. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, a rigid load supporting unit, means operable by a vertical swinging movement of the tongue when in any steering position to apply vertically a force directly to the load supporting unit of greater leverage at the beginning of the lifting movement than during the continuation thereof.

12. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, vertical and longitudinally movable load supporting means having an integral lifting head extending toward said steering mechanism and presenting a flat under-surface, a tongue extension having anti-friction roller positioned to engage the flat under-surface said lifting head and movable through an which will cause the application to said lifting head of a greater leverage at the beginning of the lifting movement than during the continuation thereof.

18. An elevating truck comprising supporting wheels and steering mechanism having a tongue mounted to swing vertically, vertical and longitudinally movable load supporting means having an integral lifting head extending toward said steering mechanism and presenting a fiat under-surface, a bell crank lifting lever detachably connected to said tongue having an antifriction roller positioned to engage thev iiat under-surface of said lifting head in a vertical plane located in proximity to the vertical plane of the fulcrum of said bell crank lever and movable upon the depression of the tongue through an arc intersecting the vertical plane of the axis of the steering mechanism whereby a greater leverage will be applied to said lifting head at the beginning of the lifting movement and during the continued movement thereof with the vertical lifting force applied to said lifting head in approximately the direction of the axis of the steering mechanism.

14. An elevating truck having a frame comprising a head, wheel-supported steering mechanism rotatably mounted therein provided with a tongue mounted to swing vertically, side-bars extending rearwardly from said head, a rear axle mounted in said sidebars, wheels mounted in said rear axle, load supporting means, substantially parallel links mounted respectively on said head and said rear axle connected respectively to the front and rear portions of said load supporting means and lifting means operable by a vertical movement of the tongue when in any steering position to engage and then to apply vertically a lifting force to the front end of said load supporting means co-operating with said lin is during the lifting of the load supporting means wholly to impose the weight of the load supporting means upon the steering mechanism and the rear axle and to maintain the front links under tension.

15. An elevating truck having a frame comprising a head, wheel-supported steering mechanism mounted therein provided with a tongue mounted to swing vertically, side-bars extending rearwardly from said head, a rear axle mounted in said side-bars, wheels rotatably mounted on said axle, load supporting means having a lifting head overlying the axis of said steering mechanism, substantially parallel front and rear links connecting said load supporting mechanism to said steering head and said rear axle, a lever detachably connected to said tongue having means operable by a vertical swinging movement of said tongue to engage said lifting head in substantially the direction of the axis of the steering mechanism and then to apply vertically a lifting force thereto whereby upon downward swinging movement of the tongue the weight of the front end of the load supporting means will be carried upon said steering mechanism and the weight of the rear end of the load will be carried directly upon said rear axle with said front links maintained under tension during the lifting movement of the load supporting` unit.

16. An elevating truck comprising supporting wheels, load supporting means, means for holding said load supporting means in elevated position, steering mechanisrn having a tongue mounted to swing vertically, a pivotally mounted lifting lever forming an extension of said tongue having means operable by a vertical swinging movement of said tongue to apply vertically a lifting force to said load supporting means, interengaging means upon said tongue and lifting lever for locking the same rigidly together automatically movable into interlocking engagement upon full upward swinging movement of the tongue and manually operable means for disengaging said locking means when the load supporting means is retained in elevated position or in lowered position to permit free steering movement from the tongue.

17. An elevating truck comprising load supporting means, supporting wheels and steering mechanism having a tongue mounted to swing vertically, a pivotally mounted lifting lever forming an extension of the tongue having a curved lower face provided at the upper portion thereof with a locking recess and having an arm underlying said load supporting means operable 'by a vertical swinging movement of the tongue to apply avertical lifting force directly to said load supporting means, a latch pivotally mounted 4on said tongue normally held in engagement with the curved face of said lifting lever and adapted automatically to engage said locking recess upon full upward swinging movement of the tongue and manually operable means for releasing said latch from operable engagement when the load supporting means is held in elevated position or is in lowered position.

18. An elevating truck comprising supporting wheels, a head having a steering mechanism rotatably mounted therein and provided with a tongue mounted to swing vertically, load supporting means movable vertically and longitudinally relatively to said head, a rigid lifting head on said load supporting means extending upwardly and centrally of the width of said load supporting Imeans and provided with a locking shoulder, lifting means releasably connected to said tongue and operable by a vertical swinging movement of said tongue to engage and lift said load supporting means, a locking dog pivotally mounted on said head, dogactuating means normally forcing said dog toward locking relation with said shoulder whereby locking will be automatically effected when the load supporting means is raised to elevated position, and manual means operable when the load supporting means is locked in elevated position to cause said dog-actuating means to exert a force upon said dog tending to move the same out of locking engagement whereby said dog will be disengaged upon a slight lifting of the load supporting means from said elevated position, and means operable by the lowering movement of the load supporting means to restore said dog to normal position.

19. An elevating truck comprising supporting wheels, a head having a steering mechanism rotatably mounted therein and provided with a tongue mounted to swing` vertically, load supporting means movable vertically and longitudinally relative to said head, a rigid lifting head on said load supporting means extending upwardly centrally of the width of said load supporting means and provided with a locking shoulder, lifting means releasably connected to said tongue and operable by a vertical swinging movement of said tongue to engage and lift said load supporting means, a locking dog pivotally mounted on said head, dog-actuating means having a spring movable across the pivotal axis of said dog and normally positioned to force said dog toward locking position and manual means operable when the load supporting means is locked in elevated position to move said spring to the opposite side of said pivot and thereby cause said spring to exert a force tending to remove said dog from locking position whereby upon raising the load supporting means from elevated position and dog will be automatically released from locking engagement.

20. An elevating truck comprising supporting wheels, a head having a steering mechanism rotatably mounted therein and provided with a tongue mounted to swing vertically, load supporting means movable vertically and longitudinally relatively to said head, a rigid lifting head on said load supporting means extending upwardly centrally of the width of said load supporting meansy and provided with a locking shoulder,

lifting means releasably connected to said tongue and operable by a vertical swinging movement of said tongue to engage and lift said load supporting means, a locking dog pivotally mounted on said head, dog-actuating means having a spring movable across CII the pivotal axis of said dog normally positioned to force said dog toward locking position and manual means operable when the load supporting means is locked in elevated position to move said spring to the opposite side of said pivot and thereby cause said spring to exert a force tending to remove said dog from locking position whereby upon raising the load supporting means from elevated position the dog will be automatically released from locking engagement, and means on said dog-actuating means adapted to be engaged by said load supporting means during the lowering movement thereof to return said spring to normal position.

21. An elevating truck comprising a frame having a head, steering mechanism rotatably mounted in said head provided with a tongue mounted to swing vertically, a rear axle rotatably mounted in said frame, wheels having anti-friction bearings rotatably mounted upon said rear axle, load supporting means, means for imparting vertical and longitudinal movement to said load supporting means i including front and rear parallel links and lifting means operable by said tongue slidably to engage and to apply vertically a lifting force directly to said load supporting means and to maintain the front links under tension, the rear pair of links being mounted upon said rotatable rear axle and adapted to cause the rotation thereof during the raising and lowering movements of said load supporting means, whereby the weight of the load supporting means will be carried by said lifting mechanism and said rear axle and the friction of said rear links reduced to a minimum by reason of the rotation of said rear axle between the anti-friction bearings of said wheels. Y

22. An elevating truck comprising a frame having a wheel supported steering mechanism, a rear axle rotatably mounted in said frame, wheels having hubs provided with anti-friction bearings rotatably mounted upon said axle, washers engaging the ends of said hubs, a spacing sleeve surrounding said axle and secured thereto and interposed between the washers on adjacent ends of said wheel hubs, load supporting means, means for imparting a vertical and longitudinal lifting movement to said load supporting means including front and rear pairs of parallel links, the rear pair of links being mounted upon said rotatable rear axle, whereby upon the lifting of said load supporting means the weight of the rear end thereof will be carried by the rotatable rear axle and said axle caused to rotate within the anti-friction bearings of said rear wheels and frictional resistance thereby reduced to a minimum.

23. An elevating truck comprising a frame having a head, side bars and a rear axle rotatablymounted in said side bars, steering mechanism rotatably mounted in said head having steeringy tongue mounted to 'swing vertically, load supporting means and means operableV by a vertical swinging movement of the tongue to move said load supporting means vertically and longitudinally, including pairs of parallel links the front pair of parallel links being pairs of bosses on load and on said head by pins, said bosses and links, having at one end a knurled head firmly seated in one of the supporting means bosses with the other end ofthe pin welded y to the frame.

24. An elevating truck comprising a frame having a head, side bars and a rear axle rotatably mounted in said side bars, steering mechanism rotatablyv mounted in said head.

inclination to the horizontal than said front links whereby the vertical movement of the ends of said load supporting means will be equalized during the raising and lowering movement thereof.

25. An elevating truck comprising load supporting means, supporting wheels therefor including steering mechanism having a tongue mounted to swing vertically and means operable thereby to lift the load supporting means, means for preventing substantial tipping of the load supporting means while the same is being lifted with the tongue at the side of the longitudinal axis of the load supporting means.

26. An elevating truck comprising load supporting means, supporting wheels, a head and steering mechanism rotatably mounted in said head having a tongue mounted to swing vertically, means operable by a vertical swinging movement of said tongue to lift said load supporting means, and a leg pivotally mounted upon and depending from a side of said head adapted to swing freely longitudinally of said load supporting means and normally held in vertical position by gravity operable to prevent substantial tipping of the load supporting means when the same is lifted with the tongue at the side of the longitudinal axis of the load supporting means.

27. An elevating truck comprising load supporting means, supporting wheels, a head and steering mechanism rotatably mounted in said head having a tongue mounted to swing vertically, means operable by a vertical swinging movement of said tongue to pivotally connected to n extending through y lift said load supporting means, and a leg pivotally mounted upon and depending from a side of said head adapted to swing freely longitudinally of said load supporting means and normally held in vertical position by gravity operable to prevent substantial tipping of the load supporting means when the same is lifted with the tongue at the side of'the longitudinal aXis of the load supporting means and means for locking said leg in a raised and inoperative position.

28. An elevating truck comprising a frame having rear wheels, a head and steering mechanism rotatably mounted therein having a tongue mounted to swing vertically, load supporting means, means operable by a vertical swinging movement of said tongue to lift said load supporting means, and legs pivotally mounted onV opposite sides of the front end of said frame depending vertically therefrom and adapted to swing freely longitudinally of said frame operable to prevent tipping of the load supporting means when the same is lifted with the tongue at the side and releasable spring-controlled means for locking the respective legs in substantially horizontal position.

In testimony whereof, I have signed my .name to this specification.

DANIEL E. IIENNESSY.

CERTIFICATE OF CORRECTION.

Patent No. 1,741,712. Granted December 31, 1929, to

DANIEL E. HENNESSY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 11), Iine 113, claim 19, for the word "and" read "the"; and that the said Letters Patent should be ,read

with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 28th day of January, A. D. 1930.

4 M. J. Moore, (Sifal) Acting Commissioner of Patents. 

